A heretofore known base structure of a collapsible baby playing bed was disclosed in U.S. Pat. No. 5,381,570, shown in FIG. 8.
This known collapsible baby playing bed is made to have various dimensions in order to be adapted for babies or children of different ages. However, when a base of this type of structure is made bigger to a certain degree, the base, when collapsed, is likely to project out of the range defined by the four corner legs resulting in the need for more space in storage and transportation.